| Cyprotex Limited | Information & communication | 2001 |
| D & S Imaging Limited | Manufacturing | 2015 |
| D N Auto Repair Ltd | Wholesale & retail | 2023 |
| D P Racing Limited | Arts & recreation | 2021 |
| D State Music Limited | Arts & recreation | 2021 |
| D the Dentist Limited | Health & social care | 2025 |
| D Vision Works Limited | Information & communication | 2000 |
| D Wheeler Extensions Ltd | Construction | 2022 |
| D&D AK Ltd | Health & social care | 2024 |
| D. Smith (Joinery) Limited | Construction | 1991 |
| DA Coaching and Consulting Ltd | Professional & scientific | 2022 |
| Dabek Bema Limited | Extraterritorial | 2024 |
| Dach Music LLP | | 2014 |
| Daisy AGE Drinks Ltd | Hospitality | 2023 |
| Dalmuir Properties Limited | Real estate | 2006 |
| Damascus Rose Cuisine Ltd | Hospitality | 2023 |
| Damascus Rose Kitchen CIC | Manufacturing | 2021 |
| Damlynhair Limited | Other services | 2025 |
| DAN Laundry Limited | Other services | 2026 |
| Dandot Promotion Limited | Health & social care | 2014 |
| Danes Convenience Store Limited | Wholesale & retail | 2016 |
| Daniel DIX Building Services Ltd | Construction | 2023 |
| Daniel Muscutt Racing Ltd | Arts & recreation | 2019 |
| Dans Garage Ltd | Wholesale & retail | 2021 |
| Dansuf Limited | Wholesale & retail | 2013 |
| Darius Communications Limited | Other services | 2021 |
| Darlington Services Ltd | Information & communication | 2025 |
| Darron COX Business Consultancy Ltd | Extraterritorial | 2023 |
| Daryl Jacob Media Services Limited | Information & communication | 2025 |
| Dash-Cae Limited | Professional & scientific | 2006 |
| Dashly Analytics Ltd | Information & communication | 2025 |
| Data Sapient Limited | Information & communication | 2021 |
| Dataclade Limited | Wholesale & retail | 2025 |
| Dataflight Solutions Ltd | Information & communication | 2024 |
| Dataplug Ltd | Information & communication | 2011 |
| Dave DIX Flooring Ltd | Other services | 2011 |
| Daventry Pubs Ltd | Hospitality | 2017 |
| Davetaucare Limited | Health & social care | 2018 |
| David and Emma Holdings Limited | Financial services | 2024 |
| David Best Courier Ltd | Transport & logistics | 2021 |
| David Crosse Corporate Services Limited | Professional & scientific | 2018 |
| David Hancox Consulting Limited | Professional & scientific | 2008 |
| David Mitchell Healthcare Consulting Limited | Health & social care | 2015 |
| David Noonan Racing Limited | Arts & recreation | 2025 |
| Davies Nuclear Associates Limited | Professional & scientific | 2012 |
| DAW Blinds Limited | Manufacturing | 2021 |
| DB22 Ltd | Professional & scientific | 2025 |
| DC Commerce Ltd | Wholesale & retail | 2025 |
| DCD Recruitment Ltd | Administrative & support | 2014 |
| DCR Favours Ltd | Wholesale & retail | 2024 |
| DCT Security Limited | Information & communication | 2024 |
| DD 3D Design Ltd | Professional & scientific | 2019 |
| DE Boer Investments UK. Ltd | Financial services | 2022 |
| Death Bear Ltd | Arts & recreation | 2025 |
| Decisive Development Ltd | Information & communication | 2021 |
| Deckle Edge Limited | Manufacturing | 2016 |
| Decko Car Service Ltd | Wholesale & retail | 2026 |
| Deeptech Recycling Limited | Manufacturing | 2022 |
| Defence Cooling Systems Limited | Professional & scientific | 2025 |
| Define Productions Ltd | Arts & recreation | 2025 |
| Definitive Entertainment Ltd | Arts & recreation | 2023 |
| Degustibus Artisan Bakery Ltd | Manufacturing | 2025 |
| Delta Violin Ltd | Information & communication | 2014 |
| Demand Economics Limited | Professional & scientific | 2012 |
| Demersys Technology Ltd | Information & communication | 2022 |
| Dench Records Limited | Information & communication | 2014 |
| Dentboost Ltd | Other services | 2019 |
| Dentistry by Thomas Limited | Health & social care | 2017 |
| Denton Brickwork Contractors Limited | Construction | 1998 |
| Denzandrenz Limited | Information & communication | 2020 |
| Dependable Social & Mental Health Limited | Professional & scientific | 2022 |
| Deso Ltd | Arts & recreation | 2024 |
| Devon Field for Dreamers Ltd | Hospitality | 2024 |
| Dexel Games Ltd | Information & communication | 2021 |
| DGB Europe Limited | Wholesale & retail | 2005 |
| DHC Technical Services Ltd | Professional & scientific | 2024 |
| DI Fontaine Recordings LLP | | 2020 |
| Diabetes Connect and Wellbeing Hub CIC | Health & social care | 2026 |
| Diamond Shine Solutions Ltd | Professional & scientific | 2013 |
| Didcot Farming Company Limited | Agriculture & fishing | 1997 |
| DIE Quelle Ltd | Professional & scientific | 2023 |
| Different Wines Limited | Wholesale & retail | 2015 |
| Digimodo Ltd | Information & communication | 2025 |
| Digimodo Studios Ltd | Information & communication | 2014 |
| Digiras Agency Ltd | Information & communication | 2024 |
| Digisoiler Ltd | Public administration | 2025 |
| Dignified Selling Ltd | Wholesale & retail | 2025 |
| Dinckley Court Limited | Hospitality | 2006 |
| Dingwall's Oxford Limited | Wholesale & retail | 2024 |
| Discuva Limited | Professional & scientific | 2007 |
| Divine Asset Management Solutions Ltd | Health & social care | 2024 |
| Divorce-Online Limited | Extraterritorial | 2005 |
| DJ Miln Ltd | Administrative & support | 2025 |
| DJS Sound Ltd | Arts & recreation | 2026 |
| DK Driver Plus Limited | Transport & logistics | 2014 |
| DM GAS Services Ltd | Construction | 2008 |
| DM Shine Solutions Limited | Administrative & support | 2018 |
| DOE Software Ltd | Wholesale & retail | 2025 |
| Dokimazo Ltd | Professional & scientific | 2024 |
| Dolphin Moblility Limited | Wholesale & retail | 2022 |